pants ci: Use correct rabbitmq service image for itests

.github/workflows/test.yaml

@@ -346,20 +346,27 @@ jobs:
       # or they require config in entrypoint args (which we can't override for GHA services)
       # bitnami builds ways to get config files from mounted volumes.
       rabbitmq:
-        image: rabbitmq:3.8-management
+        image: bitnami/rabbitmq:3.8
         volumes:
           - /home/runner/rabbitmq_conf:/bitnami/conf  # RABBITMQ_MOUNTED_CONF_DIR
         env:
           # tell bitnami/rabbitmq to enable this by default
           RABBITMQ_PLUGINS: rabbitmq_management
           RABBITMQ_USERNAME: guest
           RABBITMQ_PASSWORD: guest
+
+        # These are strictly docker options, not entrypoint args (GHA restriction)
         options: >-
           --name rabbitmq
         ports:
+          # These 6 ports are exposed by bitnami/rabbitmq (see https://www.rabbitmq.com/networking.html#ports)
+          # host_port:container_port/protocol
           - 5671:5671/tcp   # AMQP SSL port
           - 5672:5672/tcp   # AMQP standard port
           - 15672:15672/tcp # Management: HTTP, CLI
+          #- 15671:15671/tcp # Management: SSL port
+          #- 25672:25672/tcp # inter-node or CLI
+          #- 4369:4369/tcp   # epmd
 
       redis:
          # Docker Hub image